Threshold¶

rainfall_thresholds.threshold ¶

The power-law rainfall intensity-duration threshold (Caine 1980).

I(D) = alpha * D^(-beta)        I in mm/h, D in hours

A rainfall event of mean intensity I lasting D hours is above the threshold when I > I(D). Equivalently, in cumulated rainfall, E(D) = alpha * D^(1 - beta) mm.

PowerLawThreshold `dataclass` ¶

I(D) = alpha * D^(-beta), with alpha in mm/h and D in hours.

intensity ¶

intensity(duration_hours: float) -> float

The threshold mean intensity for an event of this duration, in mm/h.

cumulated ¶

cumulated(duration_hours: float) -> float

The threshold cumulated rainfall for an event of this duration, in mm.

exceedance ¶

exceedance(intensity_mm_h: float, duration_hours: float) -> float

log10(I / I(D)): decades above (positive) or below (negative) the line.

Negative infinity for a dry event (zero intensity).